title: Plethysmographic pulse wave amplitude is an effective indicator for intravascular injection of epinephrine-containing epidural test dose in sevoflurane-anesthetized pediatric patients.
abstract: BACKGROUND
  Plethysmographic pulse wave amplitude (PPWA) was effective in detecting intravascular injection of epidural test dose with 100% sensitivity and specificity in adults. We evaluated the efficacy of PPWA in detecting intravascular injection of a simulated epidural test dose during sevoflurane anesthesia in pediatric patients.
  
  
  METHODS
  Eighty infants and children were randomized to receive either 0.5 minimal alveolar concentration (MAC) or 1 MAC sevoflurane and nitrous oxide in oxygen. Patients in each anesthesia group were further randomized to receive either 0.1 mL/kg of 1% lidocaine with 1:200,000 epinephrine (0.5 mug/kg of epinephrine) IV to simulate the intravascular injection of epidural test dose or saline. Heart rate (HR), systolic blood pressure (SBP), and PPWA were monitored for 5 min after injection. A positive test response was defined as HR increase > or =10 bpm, SBP increase > or =15 mm Hg, and PPWA decrease > or =10%.
  
  
  RESULTS
  Injecting the test dose resulted in an average maximum PPWA decrease by 69% +/- 18% and 58% +/- 14% at 79 +/- 22 and 80 +/- 19 s in the 0.5 MAC and 1 MAC sevoflurane groups, respectively. The sensitivity, specificity, positive predictive, and negative predictive values for PPWA were 100% in both sevoflurane groups, whereas by using HR and SBP criteria, the sensitivity was 90% and 95% respectively during 0.5 MAC sevoflurane anesthesia and 85% for both during 1 MAC sevoflurane anesthesia.
  
  
  CONCLUSIONS
  PPWA is effective for detection of an intravascular injection of a simulated epidural epinephrine-containing test dose in pediatric patients.
authors.affiliation: Department of Anesthesiology, King Fahd University Hospital, PO Box 40081, Al-Khobar 31952, Saudi Arabia. hany_mowafi@hotmail.com
authors.forename: Hany A
authors.initials: HA
authors.lastname: Mowafi
authors.forename: Samer A
authors.initials: SA
authors.lastname: Arab
authors.forename: Salah A
authors.initials: SA
authors.lastname: Ismail
authors.forename: Abdulmohsin A
authors.initials: AA
authors.lastname: Al-Ghamdi
authors.forename: Roshdi R
authors.initials: RR
authors.lastname: Al-Metwalli
mesh_terms: D000768:Anesthesia, General; D018685:Anesthetics, Inhalation / Q000008:administration & dosage* / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004837:Epinephrine / Q000008:administration & dosage*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007223:Infant; D008738:Methyl Ethers / Q000008:administration & dosage*; D010991:Plethysmography / Q000379:methods*; D011674:Pulse; D000077149:Sevoflurane
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D004837:Epinephrine